// Declare pins and constants
const int led_red = 4;
const int led_yellow = 5;
const int led_green = 6;
const int button = 2;

int Vread;
int Vpot;
bool state = 0;

unsigned long lastDebounceTime = 0;
const unsigned long debounceDelay = 50;
bool lastButtonState = HIGH;
bool currentButtonState = HIGH;

unsigned long previousMillis = 0; // สำหรับการกระพริบ LED ใน mode2
const unsigned long interval = 1000; // หน่วงเวลา 1 วินาที

bool ledState = LOW; // สถานะของ LED ใน mode2

void setup() {
  pinMode(led_red, OUTPUT);
  pinMode(led_yellow, OUTPUT);
  pinMode(led_green, OUTPUT);
  pinMode(button, INPUT_PULLUP);

  Serial.begin(9600);
}

void loop() {
  // อ่านสถานะของปุ่มและ debounce
  bool reading = digitalRead(button);
  if (reading != lastButtonState) {
    lastDebounceTime = millis();
  }
  if ((millis() - lastDebounceTime) > debounceDelay) {
    if (reading == LOW && currentButtonState == HIGH) {
      state = !state; // สลับโหมด
      Serial.println("Mode changed to: " + String(state));
    }
    currentButtonState = reading;
  }
  lastButtonState = reading;

  // อ่านค่า potentiometer
  Vread = analogRead(A0);
  Vpot = map(Vread, 0, 1023, 0, 5); 
  Serial.println("Vpot = " + String(Vpot) + " V");

  // เรียกโหมดที่เหมาะสม
  if (state == 0) {
    mode1();
  } else {
    mode2();
  }
}

// Mode 1: ควบคุม LED ตามค่า Vpot
void mode1() {
  if (Vpot == 0) {
    digitalWrite(led_red, LOW);
    digitalWrite(led_yellow, LOW);
    digitalWrite(led_green, LOW);
  } else if (Vpot == 1) {
    digitalWrite(led_red, HIGH);
    digitalWrite(led_yellow, LOW);
    digitalWrite(led_green, LOW);
  } else if (Vpot == 2) {
    digitalWrite(led_red, LOW);
    digitalWrite(led_yellow, HIGH);
    digitalWrite(led_green, LOW);
  } else {
    digitalWrite(led_red, LOW);
    digitalWrite(led_yellow, LOW);
    digitalWrite(led_green, HIGH);
  }
}

// Mode 2: LED กระพริบทุกดวงแบบ non-blocking
void mode2() {
  unsigned long currentMillis = millis();

  if (currentMillis - previousMillis >= interval) {
    previousMillis = currentMillis;

    // เปลี่ยนสถานะ LED
    ledState = !ledState;
    digitalWrite(led_red, ledState);
    digitalWrite(led_yellow, ledState);
    digitalWrite(led_green, ledState);
  }
}